Hydraulic door closer

ABSTRACT

A hydraulic cylinder has a piston movable therein on a piston road threadably engaged in said piston. The rod extends out of the cylinder through a gland at one end and a spring is positioned between that end of the cylinder and the piston and normally urges the piston toward the other end of the cylinder which is closed. Valve means in the piston control the flow of fluid in the cylinder from either side of the piston and permit a rapid flow of fluid in one direction and a controlled flow of fluid when the piston is moved in the other direction. Rotation of the cylinder or the piston rod adjusts the controlled valving action and thereby the rate of closing action of the door closer.

United States Patent [1 1 Cain [451 Jan. 1, 1974 HYDRAULIC DOOR CLOSER[75] Inventor:

[22] Filed: June 23, 1972 [21 Appl. No.: 265,515

James P. Cain, Youngstown, Ohio [52] US. Cl. 16/52, 16/66, 188/317 [51]Int. Cl E051 3/10 [58] Field of Search 16/52, 51, 66; l37/513.4;251/122; 138/46; 188/317, 318, 319, 320

[56] References Cited 1 UNITED STATES PATENTS 3,057,004 10/1962 Sogoian137/5133 X 1,584,981 5/1926 De Hon 16/52 2,382,500 8/1945 Owens 251/122995,217 6/1911 Bishop 16/51 1,455,584 5/1923 Graham 16/66 X 3,161,90812/1964 Walach 16/52 1,151,805 8/1915 Lombard 188/320 2,996,754 8/1961Ziegler et a1 16/52 3,413,679 12/1968 Waldo 16/52 3,335,451 8/1967Patriquin 16/52 Primary ExaminerFrancis K. Zugel AssistantExaminer-Peter A. Aschenbrenner Attorney-Webster B. Harpman [5 7]ABSTRACT A hydraulic cylinder has a piston movable therein on a pistonroad threadably engaged in said piston. The rod extends out of thecylinder through a gland at one end and a spring is positioned betweenthat end of the cylinder and the piston and normally urges the pistontoward the other end of the cylinder which is closed. Valve means in thepiston control the flow of fluid in the cylinder from either side of thepiston and permit a rapid flow of fluid in one direction and acontrolled flow of fluid when the piston is moved in the otherdirection. Rotation of the cylinder or the piston rod adjusts thecontrolled valving action and thereby the rate of closing action of thedoor closer.

1 Claim, 3 Drawing Figures 1 HYDRAULIC DOOR CLOSER BACKGROUND OF THEINVENTION 1. Field of the Invention:

In its simplest form the hydraulic door closer of this This inventionrelates to hydraulic door closers of the 5 invention Comprises anelongated hydraulic cylinder type incorporating a spring for closing thedoor and a quantity of fluid, the flow of which is valved with respectto the piston to obtain a desirable rate of closure.

2. Description of the Prior Art:

Prior structures of this type have included several forms of valves,some of which may be operated by rotation of the cylinder or the pistonrod to alter the valve setting. U.S. Pat. No. 2,996,754 provides acentrally apertured piston forming the fluid passage with an extensionofthe piston receiving the piston rod and a fluid passage formed in saidextension so that the position of the piston rod relative to the fluidpassage acts as a valve element. U.S. Pat. No. 3,161,908 has the sametype of apertured piston with the extension threadably receiving thepiston rod and provides a fluid channel in the extension and parallelwith the rod with the channel terminating inwardly of the faces of thepiston so that the relative positioning of the end of the piston rodacts as a valve element. This invention mounts the piston in a threadedextension of the piston rod and provides a needle valve registry betweena portion of the piston and the piston rod for a controlled valve actionand a movable O-ring gasket for a secondary open or closed valvebypassing the needle valve.

SUMMARY OF THE INVENTION A hydraulic door closer comprises an elongatedhydraulic cylinder closed at one end with a fitting by which it may berotatably engaged on a door, has a piston movable therein and urgedtoward the closed end by a spring therein. A gland closes the other endof the cylinder with respect to a movable piston rod engaged in thepiston and extending outwardly of the cylinder and hydraulic fluid inthe cylinder moves past the piston in large volume bymeans of an O-ringbypass valve when the piston and piston rod are moved to compress thespring as in a door opening action and the fluid moves through a valvecontrolled passage in the piston with the O-ring bypass valve closedwhen the piston and piston rod are moved toward the closed end of thecylinder by the spring. Rotation of the cylinder and the piston or thepiston rod serves to reposition a needle valve configuration on thepiston rod with respect to a matching needle valve configuration in thepiston to provide an exteriorly adjustable hydraulic door closer.

DESCRIPTION OF THE DRAWINGS FIG. I is a side elevation of the hydraulicdoor closure with parts broken away and parts in cross section andshowing the door closer in fully closed position.

FIG. 2 is a side elevationwith parts broken away and parts in crosssection showing a portion of the hydraulic door closer with the pistonmoving toward the left in a door opening action, arrows indicate theflow of fluid.

FIG. 3 is a side elevation with parts broken away and parts in crosssection showing a portion of the hydraulic door closer with the pistonmoving toward the right in a door closing action with arrows indicatingthe fluid flow.

having a closure head 11 sealed in one end, the closure head having anend configuration 12 that may be rotatably positioned in a bracket on adoor (not shown). An end seal 13 is positioned in the other end of thecylinder 10 by an end seal support 14 and a tube seal 15 and acompression washer 16 form a fluid tight gland about a movable pistonrod 17. The exterior end of the piston rod 17 is apertured as at 18 sothat it can be attached to a bracket for example on a door frameadjacent a door to be closed and the other end of the piston rod 17 hasa conical section 19 formed inwardly of the end thereof so that the endportion defines an extension 20 of smaller diameter which is threaded.The threaded extension 20 of the piston rod 17 is engaged in a threadedopening 21 in a piston 22, the periphery of which has a plurality ofcircumferentially spaced passageways 23 therein communicating with anannular groove 24 in which a movable O-ring valve element 25 ispositioned. A passageway 26 is formed axially of the piston 22 and aportion thereof has a conical surface of slightly larger diameter thanthe conical section 19 of the piston rod 17.

A coil spring 27 is positioned between the compression washer 16 and theinner end of the piston 22 and normally urges the piston 22 toward thehead 11. A radially extending passageway 28 communicates with thepassage 26 and the annular groove 24 in the exterior of the piston 22.

When the head 11 and more particularly the outermost portion 12 thereofis positioned in a bracket on a door to be closed and the end of thepiston rod 17 is secured to a bracket on a door frame in which the doorto be closed is hinged, the spring 17 will move the piston 22 toward thehead 11 and thereby close the door. When the door is opened the movementof the cylinder 10 away from the piston 22 as seen in FIG. 2 of thedrawings, requires the fluid therein to flow past the piston 22 and itwill be seen that it can easily flow in relatively large volume aroundthe periphery of the piston 22 as the O-ring valve 25 will move with thefluid and away from its sealing position as seen for example in FIGS. 1and 3 of the drawings. The O-ring 25 when moved against the end of thepiston will not block the passageways 23 and the fluid flows asindicated by the arrows in FIG. 2.

By referring now to FIG. 3 of the drawings, it will be seen that whenthe spring 27 moves the piston 22 toward the closure head 11 the fluidbetween the head 11 and the piston 22 must flow to the other side of thepiston and it will therefore move through the passageways 23 into theannular groove 24. It cannot proceed around the periphery of the piston22 due to the sealing location of the O-ring valve 25 and it musttherefore flow through the passage 28 and the passage 26 and therebymove between the conical section 19 on the piston rod 17 and the conicalwall portion in the piston 22 defining the passageway 26 and as shown bythe arrows in FIG. 3 of the drawings.

It will occur to those skilled in the art that by rotating the cylinder10 while the piston rod 17 is held against rotation as by its engagementwith the bracket on the door frame as heretofore mentioned, the relativeposition of the conical section 19 of the piston rod and the conicalwall in the piston 22 defining the passageway 26 is changed so that acontrolled valving action may be readily obtained and adjusted asdesired. lt will further be seen that the adjustment directly affectsthe rate of closing action of the hydraulic door closer as imparted to adoor to which it is attached.

lt will thus be seen that a simple and efficient hydraulic door closerhas been disclosed which may be readily adjusted by rotating thehydraulic cylinder thereof so as to speed up or slow down the rate ofclosing action imparted a door by the device and it will further be seenthat no exterior valve actuating means are necessary and that theseveral parts of the hydraulic door closer disclosed herein may bereadily fabricated and assembled to produce a highly efficient,relatively inexpensive device.

Although but one embodiment of the present invention has beenillustrated and described, it will be apparent to those skilled in theart that various changes and modifications may be made therein withoutdeparting from the spirit of the invention.

I claim:

1. A door closer including a hydraulic cylinder, a piston in saidcylinder frictionally engaging the same, said piston having an axialbore, one portion of which is conical, a second portion of which is ofuniform diameter and a third portion of which is of smaller diameterthan said second portion and is threaded. a piston rod having a conicalsection inwardly of one end and an adjacent threaded extension ofsmaller diameter than said concial section threadably engaged in saidthreaded portion of said piston and closing one end of the axial bore,the other end of said piston rod extending outwardly of one end of saidcylinder, means connected to the outwardly extending end of the pistonrod to hold said rod against rotation, sealing means between saidcylinder and said piston rod, a closure in the other end of saidcylinder, a mounting bracket adapted to be fixably mounted and torotatably engage said closure, said piston having a fluid passagewaycomprised of an annular groove in the periphery of said piston inwardlyfrom the ends thereof, passage means connecting the ends of said pistonwith said annular groove, a passageway formed radially in said pistonconnecting said annular groove with said second portion of said bore,said second portion of said bore connected to a passageway formed bysaid conical portion of said rod being positioned within said conicalwall portion of said piston as the threaded extension of said rodengages the threaded portion of said piston, said passageway beingformed between said concial portions and comprising the opposite end ofsaid axial bore, the passageway through said piston being adjustable byaxial movement of said conical portion of said piston with respect tosaid conical portion of said rod as by rotation of said cylinder andpiston relative to said rod, an O-ring valve element moveably positionedin said annular groove so as to allow fluid flow into said annulargroove as piston moves in one direction and to prevent fluid flow intosaid annular groove as piston moves in the opposite direction.

1. A door closer including a hydraulic cylinder, a piston in saidcylinder frictionally engaging the same, said piston having an axialbore, one portion of which is conical, a second portion of which is ofuniform diameter and a third portion of which is of smaller diameterthan said second portion and is threaded, a piston rod having a conicalsection inwardly of one end and an adjacent threaded extension ofsmaller diameter than said concial section threadably engaged in saidthreaded portion of said piston and closing one end of the axial bore,the other end of said piston rod extending outwardly of one end of saidcylinder, means connected to the outwardly extending end of the pistonrod to hold said rod against rotation, sealing means between saidcylinder and said piston rod, a closure in the other end of saidcylinder, a mounting bracket adapted to be fixably mounted and torotatably engage said closure, said piston having a fluid passagewaycomprised of an annular groove in the periphery of said piston inwardlyfrom the ends thereof, passage means connecting the ends of said pistonwith said annular groove, a passageway formed radially in said pistonconnecting said annular groove with said second portion of said bore,said second portion of said bore connected to a passageway formed bysaid conical portion of said rod being positioned within said conicalwall portion of said piston as the threaded extension of said rodengages the threaded portion of said piston, said passageway beingformed between said concial portions and comprising the opposite end ofsaid axial bore, the passageway through said piston being adjustable byaxial movement of said conical portion of said piston with respect tosaid conical portion of said rod as by rotation of said cylinder andpiston relative to said rod, an O-ring valve element moveably positionedin said annular groove so as to allow fluid flow into said annulargroove as piston moves in one direction and to prevent fluid flow intosaid annular groove as piston moves in the opposite direction.